Saturn today, as captured by the Cassini spacecraft in 2010. The planet’s distinctive rings are only about 100 million years old. Researchers propose that they formed when the planet’s largest moon, Titan, destabilized the orbit of a smaller moon 100-200 million years ago, causing it to graze the planet and disintegrate, with a small part of the debris forming the icy, rocky rings we see today. The theory explains another Saturnian mystery — the large tilt of its rotation axis relative to its orbit. (Image credit: NASA/JPL-Caltech/Space Science Institute) Credit: NASA/JPL-Caltech/Space Science Institute / NASA